Garlic Mustard (Alliaria officinalis x 3), a lovely intruder in the cultivated mixed border, is a member of the fascinating Mustard Family (Cruciferae or Brassicaceae), Besides weeds -- often defined as "plants out of place" -- like this little rascal that rules local abandoned fields, mustards include many economic plants (cultivated by our species), including the cabbages, cauliflowers, radishes and, of couse, the mustards. Note seed pods already formed on the lower part of the indeterminate (terminal flowers open last) floral cluster.
Cute and charming as an occasional uninvited guest amongst the Giant Alliums (foreground left) and Wild Geraniums (background) in our garden, the exuberant Garlic Mustard can become a nuisance -- from the gardener's perspective -- if not kept in check.
A page from Newcomb's Wildflower Guide helps ID the weed in question (Garlic Mustard, lower right).
A mustard (not a garlic), it is so named because the leaves smell of garlic when crushed, according to the New England weed identifier's vade mecum, Newcomb's Wildflower Guide, which offers these additional keys to identification of plants with "White, Pink or Purple [4-petaled] Flowers in 1 or More Spikes or Racemes; Stem Leaves Not Arrow-shaped":
Leaves coarsely toothed, long-stalked. White flowers, 1/4-1/3" wide. Roadsides and open woods. Spring and early summer.
Pure poetry, as are the elegant line drawings. Everything that doesn't distinguish it from other species is left out. We especially enjoyed this reader's comments at ScienceDaily Books:
If you're looking for a field guide with pretty pictures of flowers, don't buy this guide. (The Audubon Society's field guide series has wonderful full-color plates.) If you're looking for a field guide which will actually help you identify flowering plants, buy this guide! I have used it for both recreational observation and scientific research purposes, and it is user-friendly and accurate.